Flexplate/converter bolts

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Jatmobkar
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Flexplate/converter bolts

Post by Jatmobkar »

My 454 flexplate is drilled for 7/16 bolts and my coan converter is 3/8. I am using 3/8-24 grade 8 bolts with washers and stover c nuts. Is this ok or should the converter be drilled for 7/16? I’d really hate to take it all back apart.
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BOOT
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Re: Flexplate/converter bolts

Post by BOOT »

I got some tube n had a friend with a band saw cut me some thin size adapters for the bolts when I had the same for a sbc. Small things like that bug me.
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Rick!
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Re: Flexplate/converter bolts

Post by Rick! »

To answer your question: No.
You will have plenty of opportunity to get the right flex plate or drill out the convertor mounts to 7/16 after the current bolts loosen up and auger out the flex plate.
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Re: Flexplate/converter bolts

Post by rebelrouser »

I think it would depend on how much torque your engine makes. If it is just a slightly over stock, no problem, if it is making 500 ft. lbs or more, I would say go to 7/16.
Most performance converters have 7/16 bolts. My experience is that many years ago when I ran a performance converter with 3/8 bolts they had a tendency to loosen up over time. When I had the converter freshened, I had them drill it to 7/16 bolts and they never came loose again. Back when they made converters out of stock cores some had 3/8 bolts, have not seen one for years that had anything smaller than 7/16.
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Re: Flexplate/converter bolts

Post by 77cruiser »

10 mm bolts on mine.
Jim
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